Born with an innate gift for harmony and composition, this Beach Boys mastermind would eventually develop and be overwhelmed by his own inner demons. Whether it was a result of the abuse of his father, a reaction to too many psychedelic drugs, or just a combination of factors, the already eccentric Wilson eventually fell into a dark place from which he may never fully return. He spent most of the 1970s and 1980s holed up in his bedroom, gorging himself on food and drugs, and listening to the torturous voices in his head. Wilson was ultimately diagnosed with schizophrenia. Fortunately, he has enjoyed a comeback this century, particularly with his critically acclaimed 2004 album Smile.

A man whose story is as strange as it is sad, Barrett was the original frontman for Pink Floyd. He recorded two albums with the band before leaving amidst speculation of mental illness. Though he managed to later produce two fine solo records and had a short stint in a band called Stars, the remainder of his life would be spent in self-imposed exile, living with his elderly mother, tending to his garden and occasionally riding around town on his bicycle. A diabetic, he died of pancreatic cancer in 2006.

Bipolar and schizophrenic, this Texan singer-songwriter's story is one of tragedy, triumph, oddity and, of course, great music. A true master of the DIY punk ethic, he also boasts a discography filled with songs that are at once catchy and sad, and are often compared to the work of his musical idols, the Beatles. A stranger-than-fiction life of legendary mental illness has come close to but has never quite overshadowed his gift for musicianship. For an essential overview of his story, look no further than the excellent 2006 documentary The Devil and Daniel Johnston.

Another Texan, this Austin-born singer-songwriter made his mark on the musical world as co-founder of the legendary garage band, the 13th Floor Elevators. The band's fame was short-lived, however, as the singer was diagnosed as paranoid schizophrenic in 1968. Though most of the next three decades of his life were marred by mental illness, shock therapy and failed escape attempts, Erickson finally found his muse again and has been enjoying a fruitful career revival since 1995. This year, he released True Love Cast Out All Evil, an excellent album on which fellow Austinites Okkervil River serve as his backing band.

The artist born Sylvester Stewart would cross genres and break barriers as the front man of the legendary band Sly and The Family Stone. His success was accompanied by a history of eccentricity, seclusion, and mysterious behavior. Though he led his band to become one of the most influential groups of the 1960s and 1970s, personal problems that speculators attribute to mental instability and drug use diminished the band and kept him out of the spotlight for decades. Sporadic recent appearances by Stone include a strange tribute performance at the 2006 Grammy Awards and a disastrous 2010 Coachella appearance.

The late, great Godfather of Soul is one of the most celebrated musicians of any era. He was also a famously eccentric, foul-tempered, and downright strange man. Though he became famous for his gritty soul songs and inimitable dance style, he would also become legendary for – among other things – a lengthy criminal history that included high-speed police chases, bizarre interview appearances and the dictatorial leadership of his band.

Probably the first superstar producer of the rock era, the "Wall Of Sound" inventor would eventually become a casualty of his own tendency towards madness. Known as a pioneer behind the mixing board in the 1960s, he would later become notorious for his obsessive producing style, often forcing artists to play the same chord literally for up to 12 hours until he was happy with the sound. He eventually became known for his obsession with guns, which would catch up with him in 2009 when he was convicted and sentenced to prison for the 2003 shooting death of actress Lana Clarkson.

This guitar legend and Fleetwood Mac founder influenced greats ranging from Jimmy Page to BB King. But Green also spent years binging on LSD and was in and out of mental hospitals, growing his fingernails bizarrely long (as you can see in the clip below). Though he still struggles to balance his psychological problems with the creativity-blocking medications he must take, Green continues to be a revered and often underrated guitar hero.

The lead singer of the Brian Jonestown Massacre is just as famous for his combative and scary personality – captured perfectly in the documentary film Dig! – as he is for his music. A perfect example of madness and musicianship combined, Newcombe is an insanely prolific writer who claims to be able to play more than 80 different instruments. He's famously aggressive (having gotten in fights with both bandmates and fans), notoriously drug-addicted, and undeniably talented.

Though not a certified madman per se, the former husband of Tina Turner undoubtedly had inner and outward struggles that veered towards madness. His life was tarnished by a history of drug use, horrific spousal abuse, infidelity, and prison. But the man was also a brilliant songwriter and arranger who, despite his low-profile death in 2007, left an indelible influence on rock and soul music.

Known for his bizarre and theatrical stage performances, in 1977, Wilson recorded his first album, You Think You Really Know Me. He would not make another one until 2003. But in the years that passed in between, he gained a cult following for his strange onstage behavior, reclusive persona, and that one beloved album. After disappearing altogether in the 1980s and 1990s, he was thought to be dead by many. In the early 2000s, Wilson was found working part-time at an adult theater by a record label on the hunt for him. Both his legacy and recording career were given new life.

Much can be said about the legendary Chicago artist, a 6-foot-plus, 300-pound man who had chronic schizophrenia and pounded out bizarre, often hilariously vulgar songs on a Casio-like keyboard. What cannot be denied is that there has never been anybody else like him. He is thought to have released over 50 albums and recorded more than a thousand songs, titles of which include "Shoot Me In The Ass," "Suck a Polar Bear's Dick," and "Alanis Morissette." He died in 2003 while suffering from leukemia, a cult icon to the public, and a rock legend in (at least) his own mind.

As the creative force behind indie legends Neutral Milk Hotel, Mangum led the outfit to record two albums, including the 1998 masterpiece, In the Aeroplane Over the Sea. Not long after that album's release, Magnum disbanded the group and disappeared from the public eye for most of the next decade. Perhaps it was the high expectations that caused him to turn his back on fame, or maybe it was just his state of mind (he once said he spent a year writing songs in a "haunted closet"). Either way, he remains legendary for both his talent and his mystery. Mangum recently gave a rare live performance in New York City, but a full comeback tour is not expected.